withdrawing from tfsa

I'm new to using tfsa... I've always been told you put money in and "lock it away" to gain interest on it (how naive). Now that I am finally doing research on how to invest properly - I was wondering how to withdraw from your tfsa without incurring extra fees?? I was considering taking my tfsa investment from rbc to pc cause of the higher interest rate, but I know I can't cause I will max my contribution room. What would be the best way to go around this (if possible?) Would moving money from my tfsa into a savings account with the same financial institution work?